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EN
The study is devoted to the possibility of increasing the efficiency of the working process in dual-fuel combustion chambers of gas turbine engines for FPSO vessels. For the first time, it is proposed to use the advantages of plasma‒chemical intensification of the combustion of hydrocarbon fuels in the dual-fuel combustion chambers, which can simultaneously operate on gaseous and liquid fuels. A design scheme of a combustion chamber with a plasma‒chemical element is proposed. A continuous type mathematical model of a combustion chamber with a plasma‒chemical element has been developed, which is based on the solution of a system of differential equations describing the processes of chemical reactions in a turbulent system, taking into consideration the initiating effect of the products of plasma‒chemical reactions on the processes of flame propagation. A modified six-stage kinetic scheme of hydrocarbon oxidation was used to simultaneously predict the combustion characteristics of the gaseous and liquid fuels, taking into account the decrease in the activation energy of carbon monoxide oxidation reactions when the products of the plasma‒chemical element are added. The results reveal that the addition of plasma‒chemical products significantly reduces CO emissions in the outlet section of the flame tube (from 25‒28 ppm to 3.9‒4.6 ppm), while the emission of nitrogen oxides remains practically unchanged for the studied combustion chamber. Further research directions are proposed to enhance the working process efficiency of a dual-fuel combustion chamber for gas turbine engines as part of the power plant of FSPO vessels.
EN
The article discusses the current state of development of supersonic transport, analyses the main limitation of the use of gas turbine engines when flying at high supersonic flight speeds, proposes a method for expanding the range of GTE limitations in these flight modes of the aircraft, using cold forcing of the engine, conducts an analytical study of the effectiveness of this approach, proposes one of the possible devices for the implementation of cold forcing, the efficiency of an engine with cold forcing is shown, which may be of significant interest for the application of cold forcing methods in gas turbine engines of supersonic transport.
EN
The article considers the methodological aspects of the theoretical investigation of marine power plants with thermochemical fuel treatment. The results of the study of the complex influence of temperature, pressure, and the ratio of steam / base fuel on the thermochemical treatment efficiency are presented. The adequacy of the obtained regression dependences was confirmed by the physical modelling of thermochemical fuel treatment processes. For a gas turbine power complex with a thermochemical fuel treatment system, the characteristics of the power equipment were determined separately with further merging of the obtained results and a combination of material and energy flow models. Algorithms, which provide settings for the mathematical models of structural and functional blocks, the optimisation of thermochemical energy transformations, and verification of developed models according to the indicators of existing gas turbine engines, were created. The influence of mechanical energy consumption during the organisation of thermochemical processing of fuel on the efficiency of thermochemical recuperation is analysed.
PL
Przedstawiono zmodyfikowaną propozycję wartościowania (ilościowego określenia) działania komór spalania turbinowych silników spalinowych z uwzględnieniem zachodzących w nich oddziaływań energetycznych. Propozycja ta uzupełnia i uściśla rozważania zawarte w publikacji [4]. Przedstawione rozważania bazują na fakcie, że w komorach spalania tego rodzaju silników spalinowych zachodzi przekształcanie energii chemicznej zawartej w dostarczonym do niej paliwie (ściślej – energii chemicznej zawartej w mieszaninie paliwowo-powietrznej powstałej w tej komorze) na energię wewnętrzną spalin i związaną z nią ich energię ciśnienia powstających podczas spalania paliwa. Ta forma przemiany energii została nazwana ciepłem (Q). Ciepło Q odniesione do jednostki czasu t spalania paliwa zostało nazwane strumieniem ciepła (Q). Przyjęto także, że w przestrzeniach między łopatkowych wirnika turbiny zachodzi proces zamiany części energii wewnętrznej spalin, ale tylko tej, którą jest energia kinetyczna ich cząstek będących w ruchu cieplnymi (czyli energia termiczna) i wynikającą z niej energię ciśnienia na energię kinetyczną ruchu obrotowego tegoż wirnika. Zwrócono uwagę, że proces ten może być nieprawidłowy, w przypadku niewłaściwego działania komory spalania. Działanie komory spalania turbinowego silnika spalinowego zostało w tym artykule zinterpretowane, jako przetwarzanie energii chemicznej spalanego paliwa na energię wewnętrzną powstających spalin w ustalonym czasie. Wartościowanie tak rozumianego działania komór spalania tego rodzaju silników spalinowych, zaproponowane w tym artykule, polega na określeniu ilościowym tego działania za pomocą wielkości fizycznej, którą cechuje wartość liczbowa z jednostka miary nazwana dżulosekundą [dżul x sekunda]. Do oceny procesu pogarszania się działania komór spalania dowolnego turbinowego silnika spalinowego zaproponowano podejście statystyczne, w którym zastosowano estymację przedziałową wartości oczekiwanej E(Qt) ciepła w chwili t oraz modele deterministyczny i probabilistyczny oceny działania komory spalania, przy czym do opracowania modelu probabilistycznego zastosowano jednorodny proces Poissona. Wspomniane ciepło jest interpretowane jako forma (sposób) przemiany w komorze spalania silnika energii chemicznej mieszaniny paliwowo-powietrznej na energię wewnętrzną i związanej z nią energię ciśnienia spalin uzyskaną podczas spalania w niej paliwa.
EN
One of the major problems in the development of algorithms for monitoring the life of aircraft gas turbine engines is that the character of loading in real flight cycles is crucially different from the character of the static and dynamic loading during the testing of samples. This paper proposes a method for taking into account the effect of retentions at maximum stresses and cycle temperatures on the low-cycle fatigue (LCF) of the heat-resistant alloys used in engine parts. Regularities in repeated-static loading (RSL) are used in combination with the method of linear accumulation of damage due to the LCF and RSL, with retentions of a variable length. A non-linear equation is derived for the summation of these damages, the solution of which determines the durability (life) of the part while taking into account the retention duration. The theoretical results were verified by using the experimental characteristics of the GS-6K and EI-437B nickel-based alloys, previously reported by other researchers.
PL
Jednym z głównych problemów w opracowywaniu algorytmów do monitorowania trwałości lotniczych gazowych silników turbinowych jest to, że charakter obciążeń powstałych w rzeczywistych cyklach lotu różni się zasadniczo od charakteru obciążeń statycznych i dynamicznych obecnych podczas testowania próbek. W niniejszej pracy zaproponowano metodę pozwalającą uwzględnić wpływ retencji przy maksymalnych naprężeniach oraz temperatur cyklicznych na zmęczenie niskocyklowe (LCF) stopów żaroodpornych używanych w elementach silnika. Wykorzystano regularności w powtarzalnym obciążeniu statycznym (RSL) w połączeniu z metodą linearnej akumulacji uszkodzeń wynikających ze zmęczenia niskocyklowego i powtarzalnego obciążenia statycznego, z retencjami o zmiennej długości. Dla sumowania tych uszkodzeń wyprowadzono nieliniowe równanie, którego rozwiązanie określa trwałość (żywotność) elementu z uwzględnieniem czasu trwania retencji. Wyniki teoretyczne zostały zweryfikowane na podstawie charakterystyk doświadczalnych stopów na bazie niklu GS-6K i EI-437B, zaczerpniętych z wcześniejszych prac innych zespołów badawczych.
EN
This study is dedicated to investigations of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. As the object of the research, a low-emission gas turbine combustion chamber with partial premixing of fuel and air inside the outer and inner radial-axial swirls was chosen. The method of the research is based on the numerical solution of the system of differential equations which represent the physical process of mass and energy conservation and transformations and species transport for a multi-component chemically reactive turbulent system, considering nitrogen oxides formation and a discrete ordinates model of radiation. The chemistry kinetics is presented by the 6-step mechanism of combustion. Seven fuel supply operating modes, varying from 100% gaseous fuel to 100% liquid fuel, have been analysed. This analysis has revealed the possibility of the application of computational fluid dynamics for problems of dual-fuel combustion chambers for the design of a floating vessel’s gas turbine. Moreover, the study has shown the possibility of working in different transitional gaseous and liquid fuel supply modes, as they satisfy modern ecological requirements. The dependencies of the averaged temperature, NO, and CO concentrations along the length of the low-emission gas turbine combustion chamber for different cases of fuel supply are presented. Depending on the different operating modes, the calculated emission of nitrogen oxides NO and carbon monoxide CO at the outlet cross-section of a flame tube are different, but, they lie in the ranges of 31‒50 and 23‒24 mg/nm3 on the peak of 100% liquid fuel supply mode. At operating modes where a gaseous fuel supply prevails, nitrogen oxide NO and carbon monoxide CO emissions lie in the ranges of 1.2‒4.0 and 0.04‒18 mg/nm3 respectively.
EN
The major effects of cylindrical and row trenched cooling holes with angles of 𝛼 = 30°, 𝛽 = 0°, 𝛼 = 40°, 𝛽 = 0° and 𝛼 = 50°, 𝛽 = 0° at BR=3.18 on the effectiveness of film cooling near the combustor end wall surface is an important subject to study in detail. In the current study, researchers used a FLUENT package 16/11 to simulate a 3-D model of a Pratt and Whitney gas turbine engine. In this research, RNG turbulence model K-ε model was used to analyze the flow behavior on the passage ways of internal cooling. In the combustor simulator, the dilution jets and cooling flow staggered in the streamwise direction and aligned in the spanwise direction as well. In comparison with the baseline case of cooling holes, the application of trenched hole near the end wall surface increased the effectiveness of film cooling up to 100% for different trench cases.
EN
This investigation is devoted to an analysis of the working process in a dual-fuel low-emission combustion chamber for a floating vessel’s gas turbine. The low-emission gas turbine combustion chamber with partial pre-mixing of fuel and air inside the outer and inner radial-axial swirlers was chosen as the object of research. When modelling processes in a dualflow low-emission gas turbine combustion chamber, a generalized method is used, based on the numerical solution of the system of conservation and transport equations for a multi-component chemically reactive turbulent system, taking into consideration nitrogen oxides formation. The Eddy-Dissipation-Concept model, which incorporates Arrhenius chemical kinetics in a turbulent flame, and the Discrete Phase Model describing the interfacial interaction are used in the investigation. The obtained results confirmed the possibility of organizing efficient combustion of distillate liquid fuel in a low-emission gas turbine combustion chamber operating on the principle of partial preliminary formation of a fuel-air mixture. Comparison of four methods of liquid fuel supply to the channels of radial-axial swirlers (centrifugal, axial, combined, and radial) revealed the advantages of the radial supply method, which are manifested in a decrease in the overall temperature field non-uniformity at the outlet and a decrease in nitrogen oxides emissions. The calculated concentrations of nitrogen oxides and carbon monoxide at the flame tube outlet for the radial method of fuel supply are 32 and 9.1 ppm, respectively. The results can be useful for further modification and improvement of the characteristics of dual-fuel gas turbine combustion chambers operating with both gaseous and liquid fuels.
EN
This article concerns the issue of thermal degradation process of fuels, important from the perspective of the operation of turbine engines, especially in the context of new fuels/bio-fuels and their implementation. The studies of the kerosenebased jet fuel (Jet A-1) and its blends with synthetic components manufactured according to HEFA and ATJ technology, were presented. Both technologies are currently approved by ASTM D7566 to produce components to be added to turbine fuels. Test rig investigations were carried out according to specific methodology which reflects the phenomena taking place in fuel systems of turbine engines. The mechanism of thermal degradation process was assessed on the basis of test results for selected properties, IR spectroscopy and calculation of activation energy. The results show that with the increase of the applied temperature there is an increment of the content of solid contaminants, water and acid for all tested fuels. Thermal degradation process is different for conventional jet fuel when compared to blends, but also semi-synthetic fuels distinguished by different thermal stability depending on a given manufacturing technology.
EN
In this paper, we consider the issue of thermo-chemical heat recovery of waste heat from gas turbine engines for the steam conversion of associated gas for offshore vessels. Current trends in the development of offshore infrastructure are identified, and the composition of power plants for mobile offshore drilling units and FPSO vessels is analyzed. We present the results of a comparison of power-to-volume ratio, power-to-weight ratio and efficiency for diesel and gas turbine power modules of various capacities. Mathematical modeling methods are used to analyze the parameters of an alternative gas turbine unit based on steam conversion of the associated gas, and the estimated efficiency of the energy module is shown to be 50%. In the modeling of the burning processes, the UGT 25000 serial low emission combustor is considered, and a detailed analysis of the processes in the combustor is presented, based on the application of a 35-reaction chemical mechanism. We confirm the possibility of efficient combustion of associated gas steam conversion products with different compositions, and establish that stable operation of the gas turbine combustor is possible when using fuels with low calorific values in the range 7–8 MJ/kg. It is found that the emissions of NOx and CO during operation of a gas turbine engine on the associated gas conversion products are within acceptable limits.
EN
The paper considers the issue of thermo-chemical recovery of engine’s waste heat and its further use for steam conversion of the associated gas for oil and gas floating units. The characteristics of the associated gas are presented, and problems of its application in dual-fuel medium-speed internal combustion engines are discussed. Various variants of combined diesel-gas turbine power plant with thermo-chemical heat recovery are analyzed. The heat of the gas turbine engine exhaust gas is utilized in a thermo-chemical reactor and a steam generator. The engines operate on synthesis gas, which is obtained as a result of steam conversion of the associated gas. Criteria for evaluating the effectiveness of the developed schemes are proposed. The results of mathematical modeling of processes in a 14.1 MW diesel-gas turbine power plant with waste heat recovery are presented. The effect of the steam/associated gas ratio on the efficiency criteria is analyzed. The obtained results indicate relatively high effectiveness of the scheme with separate high and low pressure thermo-chemical reactors for producing fuel gas for both gas turbine and internal combustion engines. The calculated efficiency of such a power plant for considered input parameters is 45.6%.
EN
To analyse the effects of cylindrical- and rowtrenched cooling holes with an alignment angle of 90 degrees on the film-cooling effectiveness near the combustor end wall surface at a blowing ratio of 3.18, the current research was done. This research included a 3D representation of a Pratt and Whitney gas turbine engine, which was simulated and analysed with a commercial finite volume package Fluent 6.2.26. The analysiswas done with Reynolds-averaged Navier-Stokes turbulence model on internal cooling passages. This combustor simulator was combined with the interaction of two rows of dilution jets, which were staggered in the streamwise direction and aligned in the spanwise direction. In comparison with the baseline case of cooling holes, using row-trenched hole near the end wall surface increased the film-cooling effectiveness 44% in average.
EN
A comparative analysis of aviation diesel and gas turbine engines in the light passenger aircraft system was conducted. Aircraft operational characteristics were obtained with the help of developed modular software system „Integration-2.1". For the formation of 5-9 seater modifications of aircraft as a prototype was taken aircraft Diamond DA42 with the location of passengers without aisle, crew consisted of 1 person. For the formation of 10-20 sealer aircrafts modifications as prototypes were taken aircrafts EV-55 and L-410UVP, the crew consisted of 2 persons, was adopted the full completion of aircraft equipment, power plant consists of two engines was adopted. It shows the economic advisability of the aircraft gas turbine engines use for airplanes of local airlines (5-6 people). It was found that the life-cycle cost of the aircraft with more passengers become lower in modifications with gas turbine engines, therefore, the use of this type of engine is advisable for aircraft with greater passenger capacity. It was found that the main factors influencing the life-cycle cost of the aircraft, are the resource characteristics of the engine, the cost of its maintenance and repair, as well as the price of fuel.
PL
Przeprowadzono analizę porównawczą lotniczych silników diesla i silników turbinowych dla lekkich samolotów pasażerskich. Eksploatacyjne charakterystyki samolotu uzyskane przez rozwinięty modułowy system oprogramowania „Integracja-2.1". Do opracowania modyfikacij 5-9 miejscowych samolotów jako punkt wyjściowy wybrano samolot Diamond DA42 z kabiną pasażerską bez korytarza i jednoosobową załogą. Do opracowania 10-20 miejscowych modyfikacji samolotów jako punkty wyjścia wybrano-samoloty EV-55 i L-410UVP, z dwuosobową załogą, przyjęty przez pełny skład sprzętu lotniczego, punkt mocy składa się z dwóch silników. Wykazano wykonalność ekonomiczną wykorzystania lotniczych turbin gazowych dla samolotów miejscowych linii lotniczych (do 5-6 osób). Stwierdzono, że koszt cyklu życiowego samolotu z wielką ilością pasażerów staje się mniejsza u modyfikacji z turbiną gazową, więc, wykorzystanie tego typu silników jest wskazane na samolotach o większej liczbie miejsc pasażerskich. Stwierdzono, że głównymi czynnikami wpływającymi na koszt cyklu życia samolotu, są cechy silnika, koszt jego utrzymania i naprawy, a także ceny paliwa.
PL
W artykule przedstawiono analizę stosowania turbinowych silników spalinowych w układach napędowych i elektrowniach jednostek pływających z uwzględnieniem aspektów ekologicznych. Zaprezentowane zostały wyniki wstępnych badań emisji związków szkodliwych spalin laboratoryjnego silnika turbinowego. Dokonano również analizy możliwości przeprowadzenia pomiarów stężeń związków szkodliwych w spalinach okrętowego turbinowego silnika spalinowego układu napędowego w warunkach jego eksploatacji na jednostce pływającej.
EN
The article presents an analysis of the use of gas turbine engines drive systems and power boats, taking into account environmental aspects. Presented preliminary results of emission of harmful exhaust of laboratory turbine engine. Also examined the possibility of carrying out measurements of concentrations of pollutants in the exhaust marine gas turbine engine propulsion system in terms of its operation on the vessel.
EN
A visual investigation of surfaces creating internal, working spaces of marine combustion engines by means of specialized view-finders so called endoscopes is at present almost a basic method of technical diagnostics. The surface structure of constructional material is visible during investigations like through the magnifying glass (usually with a precisely determined magnification), which makes possible a detection, recognition and if possible, quantitative evaluation of the failures and material defects appearing, and in result – an opinion of the waste degree and the dirt intensity of studied constructional elements. This is an especially important advantage while the failures do not generate observable values of diagnostic parameters. Endoscopic investigation of the machine being switched off from motion enables evaluation of its construc-tional elements’ waste and dirt almost at once. The paper deals with diagnostic issues concerning endoscopic examinations of the working spaces within marine diesel and gas turbine engines. In the beginning, endoscopy apparatus being on laboratory equipment of the Department of Ship Power Plants of Gdansk University of Technology in Poland has been characterized. The endoscopy considerations have been focused on theoretical bases of a digital image processing and especially - on the “Shadow” and “Phase 3D” measurement method. There has been carried out a comparative analysis of these methods’ efficiency and effectiveness in the real conditions of the diagnostic investigations performance of the engines built in the marine power plant.
PL
Badanie wizualne powierzchni tworzących przestrzenie robocze silników okrętowych z zastosowaniem specjalistycznych wzierników tzw. endoskopów to obecnie niemal podstawowa metoda diagnostyki technicznej. Struktura powierzchniowa materiału konstrukcyjnego widoczna jest podczas badań jak przez lupę, zazwyczaj w pewnym powiększeniu, co umożliwia wykrycie, rozpoznanie i ewentualną ocenę ilościową występujących defektów i wad materiałowych, które zazwyczaj nie generują obserwowalnych zmian wartości parametrów diagnostycznych. W artykule przedstawiono wybrane zagadnienia diagnostyki endoskopowej przestrzeni roboczych okrętowych turbinowych i tłokowych silników spalinowych. Scharakteryzowano endoskopową aparaturę diagnostyczną będącą na wyposażeniu bazy laboratoryjnej Katedry Siłowni Okrętowych Politechniki Gdańskiej. Przybliżono podstawy teoretyczne przetwarzania obrazu w endoskopii cyfrowej, ze szczególnym uwzględnieniem metody pomiarowej „Cienia” i „Fazowej 3D”. Przeprowadzono analizę porównawczą efektywności i skuteczności zastosowania każdej z metod w rzeczywistych warunkach realizacji badań diagnostycznych silników zabudowanych w siłowni okrętowej.
PL
Kluczowe wskaźniki efektywności (Key Performance Indicators — KPI) to jedno z podstawowych narzędzi sterowania eksploatacją obiektów technicznych. Ich właściwe wdrożenie i stosowanie pozwala na doskonalenie oraz kontrolę zarówno procesów utrzymywania, jak i użytkowania układów energetycznych. W artykule przedstawiono aspekty wykorzystania kluczowych wskaźników efektywności utrzymania w procesach sterowania eksploatacją układów energetycznych na jednostkach pływających. Wskazano istotne mierzalne wartości techniczne, organizacyjne i ekonomiczne systemów eksploatacji, które mogą determinować decyzje związane z utrzymywaniem obiektów technicznych w stanie zdatności według zamierzonych kryteriów. Dokonano przeglądu metod doboru wskaźników i podjęto próbę interpretacji ich przykładowych wartości. Odniesiono się do wykorzystania wskaźników w komputerowych systemach zarządzania utrzymaniem ruchu (Computerized Maintenance Management System — CMMS) i wykorzystania tych systemów w procesach sterowania utrzymaniem układów energetycznych.
EN
Key performance indicators (KPI) are one of basic tools used in technical objects exploitation management. Proper implementation and use of KPI make it possible to improve and control maintenance as well as operation processes of power systems. The paper presents some aspects of use of key performance indicators related to maintenance of power systems in exploitation of floating units. It includes essential measurable technical, organizational and economic values in exploitation systems which can influence decisions related to maintaining floating objects in proper conditions according to the criteria measured. The authors review the KPI selection methods and try to interpret examples of the values. It also refers to the use of KPIs in computerized maintenance management systems (CMMS) as well as to the use of these systems to control maintenance of power systems.
EN
This work is devoted to vibroacoustical condition monitoring of the gas-turbine engines (GTE) blades and diagnosis of the crack-like damages at the steady-state and non-steady-state modes of GTE. For detection of the mentioned damages we proposed the application and further development of the low-frequency vibroacoustical diagnostic methods which use vibrating and acoustical noise as diagnostic information. The following amplitude dimensionless characteristics are used as fault features: probability factor, peak factor and factor of background. The evaluation of the crack-like damage of the blades is carried out at the steady-state and nonsteady-state modes by using the generalized likelihood method. The statistical quality of the received estimations is investigated.
18
EN
Modern automated production requires technologies to provide stability in machining procedures and the absolute repeatability of the quality parameters obtained on the parts produced. Without the development of a new level of ESM procedures, the generation and implementation of technological equipment, and its complex functioning, it is impossible to produce new generation GTE for modern civil and military aircraft, as well as ships and power plants. For this purpose, issues of the technology to be created for electrochemical rotary machining of GTE blading elements have been considered, including the following aspects: features of the technology of automated GTE compressor blades manufacture, kinematic schemes of work motions of tool electrodes, and constructions of tool electrodes for electrochemical rotary machining. New engineering solutions have been offered that considerably increase the efficiency of the rotary electrochemical machining of gas turbine engine blading elements.
EN
The paper highlights the modern method of high-performance machining of geometrically complex surfaces of gas turbine engine (GTE) blades, i.e. the method of creep feed grinding. This method is widely used to machine parts made of the difficult-to-get materials, e.g. the heat-resistant nickel alloys and the cobalt based alloys applied in the production of GTE parts. The grinding process under consideration is the main technological procedure to machine the geometrically complex surfaces of turbine blade roots. It is these surfaces that determine the precise position of blades on the wheels, and correspondingly in GTE rotors and stators. The cut-maps for blade root creep feed grinding are presented, including their detailed description and guidelines in terms of their application under production conditions subject to automated production and the employment of equipment manufactured by well-known companies.
EN
The work is devoted to condition monitoring and vibroacoustical diagnosis of the crack-like damages of the gas-turbine engines (GTE) blades at the steady-state and non-steady-state modes of GTE. The developed diagnostic model of GTE is presented and the influence of damage on the measured vibro- and acoustical signals at the steady-state and non-steady-state modes of GTE is determined. The application of the following signal processing methods: Polyspectral (Higher-Order Spectral) analysis, Wavelet-transformation and dimensionless characteristics of the vibroacoustical signals is proved. The efficiency of signal processing methods is demonstrated by the results of numerical simulations of the turbine stage at the steady-state and non-steady-state modes of vibration excitation. The fault features are detected and investigated.
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